1. Beiersdorf AG, Research and Development, Unnastraße 48, D-20253 Hamburg, Germany (E.W., G.H., H.S.-L., K.-P.W., C.R.); and Department of Physical Chemistry, University of Duisburg-Essen, Campus Essen, Schuetzenbahn 70, D-45117 Essen, Germany (H.W.S.)